<em>number of waves that pass a given point in one second is called <u>frequency..</u></em>
Answer:
The magnitude of vector B is 43 units and it points in the negative y-direction.
Explanation:
Resultant of vectors = vector sum of all the vectors
Vector A = 29j
Vector B = ?
Resultant of vector A and B = R = -14j
R = A + B
-14j = 29j + B
B = -14j - 29j = - 43j
Hence, the magnitude of vector B is 43 units and it points in the negative y-direction.
The statement is false. Balanced forces can NOT change the speed OR direction of an object's motion. (See Newton's #1 law of motion.)
the friction force provided by the brakes is 30000 N.
<h3>What is friction force?</h3>
Friction force is the force that opposes the motion between two bodies in contact.
To calculate the average friction force provided by the brakes, we apply the formula below.
Formula:
- K.E = F'd............. Equation 1
Where:
- K.E = Kinetic energy of the train
- F' = Friction force provided by the brakes
- d = distance
Make F' the subject of the equation
- F' = K.E/d............ Equation 2
From the question,
Given:
Substitute these values into equation 2
- F' = (8.1 ×10⁶)/270
- F' = 30000 N
Hence, the friction force provided by the brakes is 30000 N
Learn more about friction force here: brainly.com/question/13680415